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Time Warner Cable Patents Method For Disabling Fast-Forward Function On DVRs

Posted by samzenpus on from the no-skip-for-you dept.

antdude writes in with a story about a patent that won't have DVR users skipping for joy. "Time Warner Cable has won a U.S. patent for a method for disabling fast-forward and other trick mode functions on digital video recorders. The patent, which lists Time Warner Cable principal architect Charles Hasek as the inventor, details how the nation's second largest cable MSO may be able prevent viewers from skipping TV commercials contained in programs stored on physical DVRs it deploys in subscriber homes, network-based DVRs and even recording devices subscribers purchase at retail outlets."

2 of 298 comments (clear)

  1. in lay terms by mug+funky · · Score: 5, Interesting

    this munges up the keyframes (I frames) in a stream when it detects a cue embedded by the network (ADS START HERE!!1!). therefore, if a device is designed to fast-forward by skipping over the predicted (P and B) frames, it cannot do this as it can't find the I frames needed to display anything at all.

    this will fail on sane devices because fast-forward is usually implemented as skipping just the B-frames (that are predicted off both I and P frames), while decoding the I frames and P frames.

    this will further fail because MPEG-2 decoders are fast enough that they can decode the stream in it's entirety fast enough for a practical fast-forward (my 5 yo computer can do it on CPU only, 1 core only at about 200fps).

    this will fail even further because a trivial firmware hack could detect this "cue tone" and skip the ads _entirely_. they're basically implanting a trivially readable signal that usefully tells us what are the ads and what is the show.

  2. That's not what 'digital' is for... by identity0 · · Score: 4, Interesting

    At first I was surprised that there was a new posting with the DEC logo, but then it turns out it's a newbie who doesn't know what the symbol means.

    It's summer, it's endless summer...

    Let us start a discussion of VAX and Alpha to compensate.